worktree remove: new command

This command allows to delete a worktree. Like 'move' you cannot
remove the main worktree, or one with submodules inside [1].

For deleting $GIT_WORK_TREE, Untracked files or any staged entries are
considered precious and therefore prevent removal by default. Ignored
files are not precious.

When it comes to deleting $GIT_DIR, there's no "clean" check because
there should not be any valuable data in there, except:

- HEAD reflog. There is nothing we can do about this until somebody
  steps up and implements the ref graveyard.

- Detached HEAD. Technically it can still be recovered. Although it
  may be nice to warn about orphan commits like 'git checkout' does.

[1] We do 'git status' with --ignore-submodules=all for safety
    anyway. But this needs a closer look by submodule people before we
    can allow deletion. For example, if a submodule is totally clean,
    but its repo not absorbed to the main .git dir, then deleting
    worktree also deletes the valuable .submodule repo too.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/t/t2028-worktree-move.sh b/t/t2028-worktree-move.sh
index deb486cd8e..4718c4552f 100755
--- a/t/t2028-worktree-move.sh
+++ b/t/t2028-worktree-move.sh
@@ -96,4 +96,34 @@ test_expect_success 'move worktree to another dir' '
 	test_cmp expected2 actual2
 '
 
+test_expect_success 'remove main worktree' '
+	test_must_fail git worktree remove .
+'
+
+test_expect_success 'move some-dir/destination back' '
+	git worktree move some-dir/destination destination
+'
+
+test_expect_success 'remove locked worktree' '
+	git worktree lock destination &&
+	test_when_finished "git worktree unlock destination" &&
+	test_must_fail git worktree remove destination
+'
+
+test_expect_success 'remove worktree with dirty tracked file' '
+	echo dirty >>destination/init.t &&
+	test_when_finished "git -C destination checkout init.t" &&
+	test_must_fail git worktree remove destination
+'
+
+test_expect_success 'remove worktree with untracked file' '
+	: >destination/untracked &&
+	test_must_fail git worktree remove destination
+'
+
+test_expect_success 'force remove worktree with untracked file' '
+	git worktree remove --force destination &&
+	test_path_is_missing destination
+'
+
 test_done